Magnesium alloys



Patented July 11,1939

UNITED STATES PATENT OFFICE rill No. 243,657. 193.

In Switzerland September 10,

1 Ciaim- (CL IS-108) The invention relates to a, ore-allow (master batch alloy) for the production of magnesium ,T e um alloys hitherto known for casting in sand and metal moulds do not exhibit suiiicient tensile strength'even if they are subjected to improvement, viz. quick cooling-followed by rare-heating, and they also exhibit deiects in respect of adequate ductility so that the possibility of using them is still very limited.

The defects are avoided by the use of the pre-alloy according to the invention in an amount lying within the limits of 340% and u varying in accordance with the purpose for which the resultant alloys are to be used.

The pre-alloy accordinz to the invention has the following composition:

a Percent Q (1) Aluminium 43.5-41 (2) Zinc 26' -30 (3) Manganese 1.5- 3.

(4) Nickel 3 6 (5) Steel (Siemens-Martin) 5 2 2S (6) Magnesium 21 --18 In accordance with the use of rising or falling percentages of the corresponding components 1- and 2, 4 and 5 and in accordance with the choice of the amount oi this pre-alloy' in the flnal alloy' within the range of 13-10%, the properties of the latter vary simultaneously in respect of tensile strength and ductility.

(6) Magnesium 21 Example The pro-alloy consisting of the above composition and produced in a suitable manner is added in a pre-heated condition at about 100 C. to the 5 actual magnesium melt or tothe melt of the magnesiuin alloy ii an alloy isto be improved, the

percentage added being within the prescribed limits. The added pre-alloy slowly dissolves in the melt.

I During this melting operation the customary m flux rises to the suriface and covers the melt. .when everything has become fluid the melt is thoroughly stirred 'and heated further to 800-900 C. 15 Then the crucible is removed from the furnace and after waiting some minutes for it to cool down to the casting temperature oi. NO-750 0., the alloy is cast into pigs or moulded blocks.

I claim: s As an article of new manufacture for use in the production of magnesium alloys, 9. pre-alioy oi the following composition:

v Per cent (1) Aluminium 5 435-41 p (2) zinc 26 -30 (3) Manganese 1.5- 3 (4) Nickel 3 6 (5') Steel (Siemens-Martin) 5- 2 so imrrz CHRISTEN. 

